Setting a default placeholder image WITHOUT link

<div class="imageContainer">
    <?php if ( has_post_thumbnail() ) : ?>
        <a href="https://wordpress.stackexchange.com/questions/63591/<?php the_permalink(); ?>"><?php the_post_thumbnail('size-2'); ?></a>
    <?php else : ?>
        <img src="<?php echo get_bloginfo( 'stylesheet_directory' ); ?>/images/shared/placeholder.jpg" />
    <?php endif; ?>
</div>